Keylock switch and keylock switch system

ABSTRACT

A first keylock switch and a first keylock switch system of this invention receive the supply of power from two terminals provided to the keylock switch, and output key data. Therefore, this invention can accomplish a small and reasonably-priced keylock switch and keylock switch system, drastically expand the field of application of the keylock switch, and improve security in various fields. A second keylock switch and a second keylock switch system of this invention, in particular, can also maintain the function of a conventional lock utilizing metal material. Also, this invention can isolate the signal read by read means from the power or power source stored in charge storing means to realize both supplying of power and outputting of key data through two terminals. Further, the present invention can quickly reset the state inside the keylock switches to an initial state to prepare for the next use.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to a keylock switch for transmitting keydata for actuating a locking or releasing operation to a lock devicethrough electric contact, and also to a keylock switch system using thiskeylock switch.

[0003] 2. Description of the Related Art

[0004] Locks of houses and offices, locks of car doors, locks of enginestarters, and so forth, generally employ a configuration in which ametal key that appropriately fits to a cylinder of a lock actuateslocking and releasing operations.

[0005] Electronic locks using input of a personal identification numberas a key or using storage media such as a magnetic card, an IC card, abar code label, etc, as the key have also been put into practicalapplication.

[0006] On the other hand, an identification function in automated tellermachines installed in financial institutions and a security function ofpersonal computers generally release the lock that is software-wiselocked up for a designated processing by inputting a password. Thesefunctions, too, can be regarded as an electronic keylock.

[0007] These electronic keylock each generally comprise an inputtingpart for inputting key data as an electronic key, a checking part forchecking legality of inputted key data and an operating part forexecuting a locking/releasing operation in accordance with the checkingresult.

[0008] The inputting part of the electronic keylock is so constituted asto correspond to the kind of a keylock switch which input key data. Anelectronic keylock system using the input of a personal identificationnumber as a key, for example, is equipped with a numeric keypad as theinputting part for inputting the personal identification number. Asystem using an storage media as a key includes an IC card reader, amagnetic card reader or a bar code scanner as the inputting part ofrespective systems in accordance with the kind of the storage media asthe key.

[0009] The electronic keys such as the input of the personalidentification number, the IC card, the bar code, etc, have the featurethat forging of such keys is more difficult than that of theconventional metal keys. Conventional metal keys have limited width andnumber of grooves, the shape and number of teeth, and their combination,that could be formed onto it, so the variation of metal keys istherefore limited. In contrast, an infinite number of combinations arelogically possible for keylock switches by elongating the length of thekey data. The longer the key data, the more difficult it becomes toforge the keylock switch with the result of the improvement of security.

[0010] Therefore, security of a higher level can be secured by replacingthe combination of the metal key with the metal lock by a combination ofa keylock switch with an electronic keylock or a combination of a metallock with an electronic keylock.

[0011] In practice, however, there is a limit to the length of thepersonal identification number one can bear in mind, and this in turnlimits security that is expected in the system using the input of thepersonal identification number or the password as the key.

[0012] On the other hand, the keylock switch using a storage media suchas an IC card, a magnetic card or a bar code label can store key datahaving a sufficient length. Therefore, an electronic keylock systememploying such a keylock switch is expected to provide security of highlevel.

[0013] To input the key data written to the storage media describedabove, however, both hardware and software of a large scale such as anIC card reader or a magnetic card reader are necessary.

[0014] The IC card used ordinarily, for example, has eight outputterminals for outputting in parallel the data stored in a memory in an8-bit unit. Therefore, a contact type IC card reader that is directlyconnected to the output terminals and receives the data has at leasteight input terminals and a wiring circuit for transmitting in parallelthe signals it receives to a checking part. A system that reads in anon-contact arrangement the key data stored in the memory of the IC cardmust include a radio transmission device for transmitting the key dataon the IC card and means for receiving the key data on the IC cardreader. A magnetic head and a demodulator are indispensable for themagnetic card reader. To read the bar code symbol, a bar code scannerand a demodulator are also indispensable.

[0015] As described above, the electronic keylock system using thestorage media as the keylock switch requires many system constituents,and thus is more expensive than the combination of the metal key withthe metal lock. Also, because of the need for many constituents, thereis a limit to the reduction of the size of both keylock switch andelectronic keylock.

[0016] For the reasons described above, the system using the keylockswitch and the electronic keylock has been adopted for only thoseapplications which require security of a high degree, such as researchinstitutes and factories.

[0017] On the other hand, a growing number of trespassing on small-scalebuildings such as ordinary houses and offices, theft of cars, illegaltransaction through automated teller machines, illegal utilization ofpersonal computers, and so forth, have become a serious problem inrecent years.

SUMMARY OF THE INVENTION

[0018] It is an object of the present invention to providereasonably-priced and compact keylock switch and keylock switch systemthat can guarantee safety from trespassing on small-scale buildings suchas ordinary houses and offices, theft of cars, illegal transactionthrough automated teller machines, illegal utilization of personalcomputers, and so forth.

[0019] It is another object of the present invention to drasticallyexpand the application field of a keylock switch and a keylock switchsystem by accomplishing an reasonably-priced and compact keylock switchand a keylock switch system using the keylock switch.

[0020] It is still another object of the present invention to accomplisha keylock switch that still has the function of a conventional lockformed of metal members and a keylock switch system using the keylockswitch, and apply them in fields where metal keys are widely used, toimprove security by improving the drawbacks of the metal key.

[0021] It is still another object of the present invention to quicklyreset an internal state of a keylock switch after output of key data iscompleted, to prepare for the next use.

[0022] It is a further object of the present invention to provide an artto reliably deliver only a signal representing key data from a keylockswitch to an electronic keylock, to stably detect the signalrepresenting key data in the electronic keylock.

[0023] The objects described above can be accomplished by a firstkeylock switch having a configuration in which a charge storing sectionis charged by power supplied through first and second terminals, and aread section reads key data stored in a memory by utilizing power storedin the charge storing section and outputs the key data through the firstand second terminals.

[0024] In the first keylock switch described above, the terminalsprovided to the keylock switch can be limited to only two. Therefore, itis possible to minimize both the space for the terminals themselves andthe space for wiring the terminals to circuit elements.

[0025] The objects described above can be accomplished by a secondkeylock switch having a configuration in which a keylock switch circuitcomprising a charge storing section, a memory and a read section isburied into an insulating part covering at least a part of a headportion of a metal key, a first terminal is disposed at a portion atwhich the insulating part and the metal key keep contact, and a secondterminal is disposed on a surface of the insulating part at which theinsulating part is out of contact with the metal key.

[0026] In the second keylock switch having the configuration describedabove, the metal key itself is used as the first terminal. Therefore,the number of a terminal to be disposed afresh is limited to one, and afunction of inputting key data can be added to the original function ofthe metal key itself.

[0027] The objects described above can be accomplished by a firstkeylock switch system comprising a first keylock switch and a firstelectronic keylock, the first keylock switch having a configuration inwhich a charge storing section is charged by power supplied throughfirst and second terminals, and a read section reads key data stored ina memory and outputs the key data through the first and secondterminals, the first electronic keylock including third and fourthterminals for forming one junction when they come into contact with thefirst and second terminals, respectively, a power source for supplyingpower to the keylock switch through the third and fourth terminals, anda detecting section for detecting key data from a signal inputtedthrough the third and fourth terminals.

[0028] In the first keylock switch system having the configurationdescribed above, the contacts between the first keylock switch and thefirst electronic keylock can be limited to only two points. Therefore,in both first keylock switch and first electronic keylock, it ispossible to minimize the space for the terminals themselves and thespace required for wiring the terminals to circuit elements.

[0029] The objects described above can be accomplished by a secondkeylock switch system comprising a second keylock switch and a secondelectronic keylock, the second keylock switch having a configuration inwhich a keylock switch circuit comprising a charge storing section, amemory and a read section is buried into an insulating part covering atleast a part of a head portion of a metal key, a first terminal isdisposed at a portion at which the insulating part and the metal keykeep mutual contact and a second terminal is disposed on a surface ofthe insulating part at which the insulating part is out of contact fromthe metal key, the second electronic keylock including an electronickeylock circuit comprising a third terminal so disposed as to keepcontact with a metal part contacting the metal key, a fourth terminalfor forming a junction when coming into contact with the secondterminal, a power source for supplying power to the second keylockswitch through the third and fourth terminals, and a detecting sectionfor detecting key data from a signal inputted through the third andfourth terminals.

[0030] In the second keylock switch system described above, one of thetwo junctions is formed when the metal key is inserted into the metalpart that constitutes the lock. Therefore, the number of the terminal tobe disposed afresh on the second keylock switch and on the secondelectronic lock is limited to one. Furthermore, a function of inputtingthe key data and a function of actuating a locking or a releasingoperation in accordance with the acceptance of the key data can be addedto the function that the combination of the metal key with the metallock originally has.

[0031] The objects described above can be respectively accomplished bythird and fourth keylock switches each including, in addition to thefirst or second keylock switch, a rectifying section for restrictingpower supplying directions between the first terminal and the chargestoring section and between the second terminal and the charge storingsection.

[0032] The third and fourth keylock switches having the configurationdescribed above can output the signal representing the key data storedin the memory without being affected by power stored in the chargestoring section.

[0033] The objects described above can be accomplished by a thirdkeylock switch system comprising a third keylock switch and a firstelectronic keylock and by a fourth keylock switch system comprising afourth keylock switch and a second electronic keylock.

[0034] In the third and fourth keylock switch systems having theconfigurations described above, rectification of the rectifying sectionprovided in the third or fourth keylock switch can output the signalrepresenting key data stored in the memory without being affected thepower stored in the charge storing section, and can transmit the keydata to the detecting section.

[0035] The objects described above can be accomplished by, in additionto the first or second keylock switch of the first or second keylockswitch system, a fifth or sixth keylock switch including a dischargingsection for discharging power remaining in the charge storing sectionprovided in the keylock switch, in which the discharging is done inaccordance with opening the two contacts formed between the keylockswitch and the electronic keylock.

[0036] In the fifth and sixth keylock switches respectively having theconfigurations described above, the discharging section discharges powerremaining in the charge storing section in accordance with the releaseof the junction between the keylock switch and the electronic keylock.Therefore, each component in the keylock switch can be quickly reset, sothat the keylock switch can be ready for the next junction.

[0037] The objects described above can be accomplished by, in additionto the first electronic keylock provided to the first keylock switchsystem or the second electronic keylock provided to the second keylockswitch system, third and fourth electronic keylocks each including anisolating section for isolating an AC signal appearing between the thirdand fourth terminals from the power source.

[0038] Since the third and fourth electronic keylocks described aboveinclude the isolating section, the read section can transmit to thedetecting section the signal outputted through the two junctions withoutbeing affected by the power source.

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The nature, principle, and utility of the invention will becomemore apparent from the following detailed description when read inconjunction with the accompanying drawings in which like parts aredesignated by identical reference numbers, in which:

[0040]FIG. 1 shows the principle of a first keylock switch and a firstkeylock switch system using the first keylock switch according to thepresent invention;

[0041]FIG. 2 shows the principle of a second keylock switch and a secondkeylock switch system using the second keylock switch according to thepresent invention;

[0042]FIG. 3 shows the first embodiment of the first keylock switchaccording to the present invention;

[0043]FIG. 4 explains an operation of transmitting key data;

[0044]FIG. 5 shows an embodiment of the second keylock switch accordingto the present invention;

[0045]FIG. 6 shows the first embodiment of the second keylock switchsystem when the second keylock switch having a built-in keylock switchcircuit is used in combination with a lock of a door;

[0046]FIG. 7 shows the second embodiment of the second keylock switchsystem when the second keylock switch having a built-in electronickeylock switch circuit is used in combination with a lock of a door;

[0047]FIG. 8 shows the third embodiment of the second keylock switchsystem according to the present invention;

[0048]FIG. 9 shows the second embodiment of the first keylock switchaccording to the present invention;

[0049]FIG. 10 shows the third embodiment of the first keylock switchsystem applied to a automated teller machine; and

[0050]FIG. 11 shows a flowchart of an automated teller machine using akeylock switch.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0051] [Principle]

[0052] First, explanation is given on the principle of a keylock switchand a keylock system according to the invention.

[0053]FIG. 1 shows the principle of a first keylock switch and that of afirst keylock switch system using this keylock switch according to thepresent invention.

[0054] The first keylock switch shown in FIG. 1 comprises a firstterminal 101, a second terminal 102, a charge storing section 111, amemory 112 and a read section 113.

[0055] The principle of the first keylock switch according to thepresent invention is as follows.

[0056] The first terminal 101 and the second terminal 102 are electriccontacts. The charge storing section 111 is connected between the firstterminal 101 and the second terminal 102 and is charged by powersupplied through these first and second terminals 101 and 102. Thememory 112 stores key data having a predetermined length. The readsection 113 receives the supply of power stored in the charge storingsection 111, reads out the key data stored in the memory 112 and outputthis key data through the first and second terminals 101 and 102.

[0057] The first keylock switch having such a configuration operates inthe following way.

[0058] The charge storing section 111 is charged by power suppliedthrough the first and second terminals 101 and 102. The read section 113reads out the key data stored in the memory 112 by using power stored inthe charge storing section 111 and outputs the key data through thefirst and second terminals 101 and 102. In consequence, the supply ofpower to the keylock switch and the output of the key data can beachieved by having only two contacts.

[0059]FIG. 2 shows the principle of a second keylock switch according tothe present invention and the principle of a second keylock switchsystem using this keylock switch according to the present invention.

[0060] The second keylock switch shown in FIG. 2 comprises a metal key103, an insulating part 104 and a keylock switch circuit 105. Thekeylock switch circuit 105 includes a charge storing section 111, amemory 112, a read section 113, a first terminal 101 and a secondterminal 102.

[0061] The principle of the second keylock switch according to thepresent invention is as follows.

[0062] The metal key 103 operates mechanical components provided to alock. The insulating part 104 covers at least a part of a head portionprovided to the metal key 103. A keylock switch circuit 105 disposedinside the insulating part 104 includes a first terminal 101 disposed atthe contact portion between the insulating part 104 and the metal key103, a second terminal 102 disposed on the surface of the insulatingpart 104 that is out of contact from the metal key 103, a charge storingsection 111 connected between the first terminal 101 and the secondterminal 102, for being charged by power supplied through these firstand second terminals 101 and 102, a memory 112 for storing key datahaving a predetermined length and a read section 113 for receiving thesupply of power stored in the charge storing section 111 and reading thekey data stored in the memory 112 and outputting the key data throughthe first and second terminals 101 and 102.

[0063] The second keylock switch having such a configuration operates inthe following way.

[0064] In the keylock switch circuit 105 buried into the insulating part104 covering at least a part of the head portion of the metal key 103,the charge storing section 111 is charged by power supplied through thefirst terminal 101, that is disposed at the contact portion between theinsulating part 104 and the metal key 103, and through the secondterminal 102 disposed on the surface of the insulating part 104 that isout of contact from the metal key 103. The read section 113 reads outthe key data stored in the memory 112 by using power stored in thecharge storing section 111 and outputs the key data through the firstand second terminals 101 and 102. In this way, the metal key 103 itselfcan be utilized as the first terminal.

[0065] The first keylock switch system shown in FIG. 1 comprises thefirst keylock switch and a first electronic keylock. The first keylockswitch comprises a first terminal 101, a second terminal 102, a chargestoring section 111, a memory 112, and a read section 113. The firstelectronic keylock comprises a third terminal 106, a fourth terminal107, a power source 121 and a detecting section 122.

[0066] The principle of the first keylock switch system according to thepresent invention is as follows.

[0067] In the first keylock switch, the first terminal 101 and thesecond terminal 102 are electric contacts. The charge storing section111 is connected between the first terminal 101 and the second terminal102 and is charged by power supplied through the first and secondterminals 101 and 102. The memory 112 stores key data having apredetermined length. The read section 113 receives the supply of powerstored in the charge storing section 111, reads the key data stored inthe memory 112 and outputs the key data through the first and secondterminals 101 and 102. The first electronic keylock includes twojunctions when coming into contact with the first and second terminals101 and 102, a power source 121 for supplying driving power to thekeylock switch through the third and fourth terminals 106 and 107, and adetecting section 122 for detecting the key data from a signal appearingbetween the third and fourth terminals 106 and 107.

[0068] The first keylock switch system having the configurationdescribed above operates in the following way.

[0069] The first and second terminals 101 and 102 of the first keylockswitch are brought into contact with the third and fourth terminals 106and 107 of the first electronic keylock to form two junctions. Thecharge storing section 111 is charged by power supplied from the powersource 121 which is provided to the electronic keylock through thesejunctions. The read section 113 reads out the key data stored in thememory 112 by using power stored in the charge storing section 111 andoutputs the signal representing the key data through the two junctions.The detecting section 122 detects the key data from this signal.

[0070] The second keylock switch system shown in FIG. 2 has a secondkeylock switch which includes a metal key 103, an insulating part 104, akeylock switch circuit 105, and a second electronic keylock which has ametal part 108 and an electronic keylock circuit 109. The keylock switchcircuit 105 includes a first terminal 101, a second terminal 102, acharge storing section 111, a memory 112, and a read section 113. Theelectronic keylock circuit 109 includes a third terminal 106, a fourthterminal 107, a power source 121, and a detecting section 122.

[0071] The principle of the second keylock switch system according tothe present invention is as follows.

[0072] In the second keylock switch, the metal key 103 is for operatingmechanical components provided to a lock, and includes an insulatingpart 104 that covers at least a part of the head portion of the metalkey 103. In the keylock switch circuit disposed inside the insulatingpart 104, the first terminal 101 is disposed at a contact portionbetween the insulating part 104 and the metal key 103, and the secondterminal is disposed on the surface of the insulating part 104 that isout of contact from the metal key 103. The charge storing section 111 isconnected between the first terminal 101 and the second terminal 102,and is charged by power supplied through these first and secondterminals 101 and 102. The memory 112 stores key data having apredetermined length. The read section receives the supply of powerstored in the charge storing section 111, reads the key data stored inthe memory 112 and outputs the key data through the first and secondterminals 101 and 102. In the second electronic keylock, on the otherhand, the third terminal 106 is so disposed as to keep contact with themetal part 108 that in turn keeps contact with the metal key 103. Thefourth terminal 107 comes into contact with the second terminal 102 andforms one of junctions. The power source 121 feeds driving power to thekeylock switch through the third and fourth terminal 106 and 107. Thedetecting section 122 detects the key data from a signal appearingbetween the third terminal 106 and the fourth terminal 107.

[0073] The second keylock switch system having the configurationdescribed above operates in the following way.

[0074] The first terminal 101 disposed at the part making contactbetween the insulating part 104 and the metal key 103 and the secondterminal 102 disposed on the surface of the insulating part 104 that isout of contact from the metal key 103 are brought into contact with thethird and fourth terminals 106 and 107 provided to the second electronickeylock, respectively, forming two junctions. The charge storing section111 is charged by a power supplied from the power source through thesejunctions. The read section 113 reads out the key data stored in thememory 112 by using this power and outputs the signal representing thekey data through the two junctions.

[0075] The detecting section 122 detects the key data from this signal.

[0076] The third keylock switch shown in FIG. 1 includes a first keylockswitch and a rectifying section 114. The principle of the third keylockswitch according to the present invention is as follows.

[0077] The rectifying section 114 restricts the power supplyingdirection between the first terminal 101 and the charge storing section111 and between the second terminal 102 and the charge storing section111.

[0078] The third keylock switch having the configuration described aboveoperates in the following way.

[0079] Rectification of the rectifying section 114 restricts thedirection of the power supply in the circuit comprising the firstterminal 101, the second terminal 102, and the charge storing section111, and can prevent back-flow of the charge stored in the chargestoring section 111.

[0080] Also, the second keylock switch shown in FIG. 2 and therectifying section 114 described above together constitute a fourthkeylock switch.

[0081] Since the principle of the fourth keylock switch and itsoperation are analogous to those of the third keylock switch describedabove, explanation is hereby omitted.

[0082] The third keylock switch system shown in FIG. 1 includes a firstelectronic keylock and a third keylock switch, and the third keylockswitch includes a first keylock switch and a rectifying section 114.

[0083] The principle of the third keylock switch system according to thepresent invention is as follows.

[0084] The rectifying section 114 provided to the third keylock switchrestricts the power supplying direction between the first terminal 101and the charge storing section 111 and between the second terminal 102and the charge storing section 111.

[0085] The third keylock switch system having the configurationdescribed above operates in the following way.

[0086] Rectification of the rectifying section 114 restricts the powersupplying direction in the circuit including the first terminal 101, thesecond terminal 102, and the charge storing section 111 with the resultthat the power supplying direction between the charge storing section111 and the power source is also restricted.

[0087] Incidentally, the second electronic keylock shown in FIG. 2 andthe third keylock switch described above together constitute a fourthkeylock switch system.

[0088] Since the principle of the fourth keylock switch system and itsoperation are analogous to those of the third keylock switch systemdescribed above, the explanation is hereby omitted.

[0089] A fifth keylock switch shown in FIG. 1 includes a first keylockswitch provided to a first keylock switch system and a dischargingsection 115.

[0090] The principle of the fifth keylock switch according to arts thepresent invention is as follows.

[0091] The discharging section 115 discharges power remaining in thecharge storing section 111 provided to the first keylock switch when thejunctions formed by the first and second terminals 101 and 102 providedto the first keylock switch and the third and fourth terminals 106 and107 provided to the first electronic keylock are released.

[0092] The fifth keylock switch having the configuration described aboveoperates in the following way.

[0093] As the two junctions are released, the discharging section 115discharges power remaining in the charge storing section 111.

[0094] Incidentally, the second keylock switch provided to the secondkeylock switch system shown in FIG. 2 and the discharging section 115described above together constitute a sixth keylock switch.

[0095] Since the principle of this sixth keylock switch and itsoperation are analogous to those of the fifth keylock switch describedabove, the explanation is hereby omitted.

[0096] A third electronic keylock shown in FIG. 1 includes a firstelectronic keylock and an isolating section 123.

[0097] The principle of the third electronic keylock according to thepresent invention is as follows.

[0098] In the third electronic keylock, the isolating section 123isolates an AC signal appearing between a third terminal 106 and afourth terminal 107 from a power source 121.

[0099] The third electronic keylock having the configuration describedabove operates in the following way.

[0100] The isolating section 123 isolates the AC signal appearingbetween the third terminal 106 and the fourth terminal 107 from thepower source 121, so therefore transmits the signal to only thedetecting section 122.

[0101] Incidentally, the second electronic keylock shown in FIG. 2 andthe isolating section 123 described above together constitute a fourthelectronic keylock. Since the principle of this fourth electronickeylock and its operation are analogous to those of the third electronickeylock described above, the explanation is hereby omitted.

[0102] [Embodiment]

[0103] Embodiments of the present invention will be explained in detailwith reference to the accompanying drawings.

[0104]FIG. 3 shows a first keylock switch according to the firstembodiment of the present invention.

[0105] In the keylock switch circuit 210 shown in FIG. 3, one of theterminals A, that constitutes a junction indicated by symbol A isconnected in parallel with an anode of a diode 211 and a collector of atransistor 212. One of the ends of a capacitor 213 and a collector of atransistor 214 are connected in parallel with a cathode of the diode 211described above. The other end of this capacitor 213 is connected to oneof the terminals B, that constitute a junction indicated by symbol B asshown in FIG. 3. Emitters of both transistors 212 and 214 are connectedto this terminal B₀ through resistors, respectively.

[0106] A voltage monitoring part 215 shown in FIG. 3 monitors apotential difference between both ends of the capacitor 213 describedabove, and controls ON/OFF the transistor 214 as well as the readoperation by a read circuit 216 on the basis of the comparison result ofthe potential difference with a predetermined threshold. The readcircuit 216 serially reads out the key data stored in a memory 217 andinputs this read signal to the base of the transistor 212.

[0107] On the other hand, a power source 221 provided to an electronickeylock circuit 220 shown in FIG. 3 is connected to the other terminalA₁ constituting the junction A through an impedance that is included inan impedance circuit 222. A signal inputted through this terminal A₁ isinputted to a signal detecting part 223. The other terminal B₁constituting the junction B is grounded in this electronic keylockcircuit 220.

[0108] Next, explanation is given on an operation of transmitting thekey data from the keylock switch circuit to the electronic keylockcircuit each having the configuration described above.

[0109]FIG. 4 explains an operation of transmitting the key data.

[0110] When the junction terminals A₀, A₁ and B₀, B₁ are contacted,respectively, the supply of power is started from the power source 221provided to the electronic keylock circuit 220 to the keylock switchcircuit 210 through the junction A, as the charge is stored in thecapacitor 213. In consequence, the potential difference between thejunction A and the junction B increases with the potential difference atboth ends of the capacitor 213 (see FIG. 4(a)).

[0111] When the potential difference at both ends of the capacitor 213exceeds a predetermined potential difference Dts, the voltage monitoringpart 215 instructs the read circuit 216 to start the read operation. Inresponse to this instruction, the read circuit 216 starts reading a keycode including a certain key data stored in the memory 217. When thetransistor 212 is controlled ON/OFF in accordance with the read signalobtained by the read circuit 216, the signals representing the key codeare transmitted as the potential difference alternating between thejunctions A and B to the electronic keylock circuit 220 as shown in FIG.4(a).

[0112] When the junctions A and B are disconnected after the signals arethus transmitted, as shown in FIG. 4(a), the alternation in thepotential difference at both ends of the capacitor gradually decreases.When the potential difference becomes lower than the predeterminedthreshold Dte, the voltage monitoring part 215 judges that theconnection between the keylock switch and the electronic keylock isreleased. At this time, the transistor 214 is turned ON in accordancewith the signal inputted by this voltage monitoring part 215 to the baseof the transistor 214. As the transistor 214 is thus turned ON, thecharge stored in the capacitor 213 is compulsively discharged. Next,each part of the keylock switch circuit 210 is initialized so as toprepare for the occasion at which the keylock switch circuit 210 and theelectronic keylock circuit 220 are connected next to each other.

[0113] The signal indicating the alternation in the potential differenceof junctions A and B according to the ON/OFF of transistor 212(hereonafter called an ON/OFF signal) is isolated from the power source221 by the impedance as a constituent element of the impedance circuit222 provided to the electronic keylock circuit 220. Also, rectificationof the diode 211 provided to the keylock switch circuit 210 isolates theON/OFF signals from capacitor 213, too. Therefore, it is possible tostably transmit the ON/OFF signal, which is a square wave as shown inFIG. 4(a), to the electronic keylock circuit 220 by utilizing in commonthe junctions A and B used for the supply of power.

[0114] By employing a programmable ROM as the memory 217, it is possibleto store the key code comprising a start bit, 64-bit key data and a stopbit, for example, by inputting the key code through a write terminal 218during the production process of the keylock switch. The read circuit216 serially reads out the key data so stored in the memory 217 inaccordance with a predetermined clock, and transmits the key data by theON/OFF signal described above to the electronic keylock circuit 220through the junctions A and B. A signal detecting part 223 provided tothe electronic keylock circuit 220 first digitizes the ON/OFF signal onthe basis of a predetermined threshold, then reproduces the key data byapplying start-stop transmission to the key code. As shown in FIG. 4(b),for example, the function of the signal detecting part 223 can beaccomplished by inputting the ON/OFF signal inputted through theterminal A₁ to a comparator and inputting the output of this comparatorto a serial input port (shown as a serial port in the drawing) of theprocessor. Then key data can be acquired from the output port of thisprocessor.

[0115] As described above, the keylock switch circuit 210 and theelectronic keylock circuit 220 are connected at the two junctions A andB so that power is supplied to the keylock switch through these twojunctions A and B, and the key data held by the keylock switch circuit210 can be delivered to the electronic keylock circuit 220.

[0116] In this way, the present invention can accomplish the keylockswitch circuit that is by far more reasonably-priced and smaller in sizethan the conventional circuits using the IC card interface. Therefore,the present invention can drastically expand the application field ofthe keylock switch.

[0117]FIG. 5 shows the second keylock switch according to the presentinvention.

[0118] As shown in FIG. 5(a), for example, a key IC produced byintegrating a keylock switch circuit is buried into a molded partcovering a head portion of a metal key. A junction B is formed byutilizing the contact between the metal key itself and a metal part of acylinder in a lock, and a terminal A₀ constituting a junction A isformed on the surface of the molded part. A contact point that iselectrically insulated from the metal part of the cylinder is formed onthe surface of the lock (see FIG. 5(c)). This contact point and themetal part of the cylinder are connected as terminals A₁ and B₁ of anelectronic keylock circuit (see FIG. 5(b)). In this way, the key datacan be transmitted from the keylock switch circuit built in the moldedpart of the metal key to the electronic keylock circuit built in thelock.

[0119] When such a configuration is adopted, the keylock switch systemcan be applied to the fields in which the metal keys have been utilizedgenerally, such as ordinary houses, offices and vehicles.

[0120]FIG. 6 shows the first embodiment of a second keylock switchsystem using a second keylock switch having a built-in keylock switchcircuit in combination with a lock of a door.

[0121] Referring to FIG. 6, the locking mechanism of the door isoperated by a metal key inserted into the cylinder provided in the lock.In this operation, through junction A and junction B which is formed bythe contact of the metal key and the metal part of the cylinder, thesupply of power to the key IC and the transmission of the key data fromthe key IC to the electronic keylock circuit 220 can be made.

[0122] When the keylock switch is inserted into the cylinder, the signaldetecting part 223 detects the key data from the signal transmittedthrough the junctions A and B, and this key data is inputted to acomparing circuit 231. The comparing circuit 231 compares the key dataso inputted with reference key data stored in advance in a key datamemory 232 and judges whether or not they coincide with each other. Whenthe comparing circuit 231 judges that the input key data is notcoincident with the reference key data, an audio output controlling part233 inputs a predetermined alarm sound signal to a speaker 234.

[0123] Therefore, even when the releasing operation on a lock provessuccessful by a dishonest means that uses a key duplicating the form ofan authentic metal key, for example, by detecting that the key data arenot coincident, it can be judged that this releasing operation isunauthorized, and to raise an alarm from the speaker 234.

[0124]FIG. 7 shows the second embodiment of the second keylock switchsystem using the second keylock switch having a built-in keylock switchcircuit in combination with the lock of the door.

[0125] In this way, a keylock switch system equipped with anelectromagnetic control keylock 235 together with a cylinder operated bya metal key can be constituted as a locking mechanism of the door.

[0126] The second keylock switch system shown in FIG. 7 includes anelectromagnetic control keylock controller 236 in place of the audiooutput controlling part 233 and the speaker 234 shown in FIG. 6. Onlywhen the comparing circuit 231 judges that the input key data coincideswith the reference key data, this electromagnetic control keylockcontroller 235 releases the electromagnetic lock 235.

[0127] When the keylock switch including the metal key and theelectromagnetic control keylock are combined as described above, itbecomes possible to prevent the unfair releasing operation so long asboth of the form of the metal key and the key data transmitted from thekey IC to the keylock switch circuit 220 do not coincide.

[0128] In any case, transmission of the key data is automaticallyexecuted when the keylock switch is inserted into the cylinder providedin the lock. As long as a keylock switch having a built-in key ICstoring valid key data is used, no additional operation is necessaryother than the normal releasing operation. Therefore, security of thelocks provided to ordinary houses and the like can be improved whileconvenience similar to that of the conventional metal keys is insured.

[0129] The keylock switch systems described above can be appliedsimilarly to locks provided to the doors of vehicles and ships, or startmechanism of their engines.

[0130] When the engines of vehicles and ships, for example, include anobject to be electrically controlled, predetermined limitation can beapplied to the operation of the control object when validity of the keydata received from the keylock switch is denied.

[0131]FIG. 8 shows the third embodiment of the second keylock switchsystem according to the present invention.

[0132] As shown in the drawing, the judgment result by the comparingcircuit 231 is inputted to an electronic fuel injection controller(indicated as an EFI controller in the Figure) 237 equipped withvehicles. When the judgment result represents that the reference keydata does not coincide with the input key data, the electronic fuelinjection controller 237 may execute control so as to limit the quantityof the fuel supply for the engine 238 to a level below a predeterminedquantity.

[0133] In this case, the quantity of the fuel supplied to the engine 238is limited even when the engine 238 starts operating due to the startingoperation by the metal key. Therefore, the car cannot run at a speedexceeding a predetermined speed. In consequence, it becomes possible toimprove safety of the locks of cars in general and to prevent the theftof the cars while keeping convenience equivalent to that of theconventional metal keys.

[0134] Next, explanation is given on a keylock switch suitable for thefields in which so-called “metal keys” have not been utilized in thepast.

[0135]FIG. 9 shows the second embodiment of the first keylock switch.

[0136] As shown in FIG. 9(a), a key IC is buried into a seal impressionformed of an insulating material such as a resin.

[0137] A terminal A, for forming a junction A is formed on the oppositeside to the seal impression, and a ring-like terminal B. is formed roundthe insulating material that forms the seal impression. A ring-likecontact that comes into contact with the terminal B₀ to form a junctionB and a contact that comes into contact with the contact A₀ are formedinside the socket that fits to the seal impression. These contacts areconnected to terminals B₁ and A₁ of the electronic keylock circuit,respectively. In this way, the key data can be transmitted from thekeylock switch circuit built in the seal impression to an electronickeylock circuit.

[0138] By employing the configuration described above, the keylockswitch system can be applied as a security protection system in thefields that have exclusively relied on the input of personalidentification numbers or passwords such as confirmation in automatedteller machines and identification in utilizing personal computers. Inthis case, an input part such as an operation panel or a keyboard eachhaving a socket described above may be constituted as shown in FIG.9(b), for example.

[0139] Next, explanation is given on a concrete example of the keylockswitch system using such a keylock switch.

[0140]FIG. 10 shows the third embodiment of the first keylock switchsystem applied to an automated teller machine.

[0141] In FIG. 10, a socket for a keylock switch, and an l electronickeylock circuit 220, are provided to an operation panel of an automatedteller machine together with an input device such as a touch panel 241.

[0142] When an keylock switch mounted signet having a built-in key IC isinserted into the socket, a signal detecting part 223 provided to theelectronic keylock circuit 220 detects key data from the signaltransmitted from the key IC to the electronic keylock circuit 220through the junctions A and B. This key data is inputted to a comparingpart 243 through an input-output controller 242 (indicated as an I/Ocontroller in the Figure) provided to the automated teller machine. Theinput data from the touch panel 241 described above and read data by amagnetic card reader 245 provided to the automated teller machine aredelivered to a transaction controlling part 244 through the input-outputcontroller 242.

[0143] In addition to a conventional customer information file 246 forstoring customer information corresponding to an account number, theautomated teller machine shown in FIG. 10 includes a key data file 247for storing key data corresponding to the customer account number. Thesecustomer information and key data are delivered to the transactioncontrolling part 244 and the comparing part 243 for processing.

[0144] The automated teller machine further includes a display devicesuch as a liquid crystal display (indicated as a DISP in the Figure)248. The input-output controller 242 controls the operation of theliquid crystal display 248 in accordance with the instruction from thetransaction controlling part 244 to thereby offer the transactioninformation to the customers.

[0145] Next, explanation is given on the operation of the automatedteller machine.

[0146]FIG. 11 is a flowchart showing the operation of the automatedteller machine using the keylock switch.

[0147] First, a magnetic card reader 245 reads the customer accountnumber from a cash card (step 301) in the same way as the processing ina conventional automated teller machine. Next, the transactioncontrolling part 244 executes identification (step 302) on the basis ofthe customer identification number registered to the customerinformation file 246 corresponding to the account number and thecustomer's personal identification number(indicated as PIN in theFigure) inputted from the touch panel 241.

[0148] When this identification result proves true (YES instep 303), theflow proceeds to step 304, where the instruction on the transaction isreceived through the touch panel 214, and the transaction controllingpart 244 judges whether or not the transaction so instructed istransaction of a large sum requiring further identification on the basisof the content of the instruction (step 305).

[0149] When the judgment result proves true (YES in step 305), theinput-output controller 242 controls the display operation of the liquidcrystal display 248 in accordance with the instruction from thetransaction controlling part 244 to let it display a message calling forthe insertion of the keylock switch mounted signet (step 306).

[0150] When the keylock switch mounted signet is inserted into thesocket shown in FIG. 10 in accordance with this message, the comparingpart 243 receives the key data from the signal detecting part 223 of theelectronic keylock circuit 220, and compares it with the key data soregistered to the key data file 247 as to correspond to the accountnumber notified from the transaction controlling part 244 (step 307).When the inputted key data and the key data registered to the key datafile 247 are coincident (YES in step 308), the transaction controllingpart 244 judges that identification is duly made on the basis of the keydata, executes the transaction processing in accordance with theinstruction inputted in step 304 (step 309) and finishes the processing.

[0151] When the judgment result in step 308 or step 303 proves NO, onthe other hand, the flow proceeds to step 310, where an appropriatealarm processing is executed as identification fails. The processing isthus completed.

[0152] When the judgment result proves NO in step 305, the flow proceedsto step 309 while the steps from 306 to 308 are skipped, and theinstructed transaction is executed and is then finished in the same wayas in the prior art system.

[0153] The keylock switch mounted signet shown in FIG. 9 is very smalland very convenient to carry. Moreover, the deed of inserting such ankeylock switch mounted signet into the socket is analogous to putting ofone's seal in financial institutions and is rather familiar tocustomers. In comparison with the case where a customer is required toinput a password in addition to the personal identification number, thissystem can drastically reduce the burden to the customer. Though thenumber of digits is so small that the customer can easily bear it inmind, identification can be made on the basis of the key data usingsufficient length.

[0154] Therefore, safety of the transaction of the large sum can beimproved by executing identification by the keylock switch mountedsignet in addition to identification by the ordinary personalidentification number, without increasing the burden to the customer.

[0155] Incidentally, the keylock switch circuit described above can beintegrated into an extremely small key IC, and it can be sufficientlyburied into a small seal used frequently in the daily life or into awriting instrument such as a ball-point pen.

[0156] In this case, for example, an electronic keylock circuit may beprovided in a personal computer, and a socket that fits a junctionterminal formed on a keylock switch mounted pen may be provided on akeyboard of the personal computer. By fitting the keylock switch mountedpen having the key IC buried therein into the socket provided on thekeyboard, the key data are transmitted through the socket from the keyIC to the electronic keylock circuit. By the processing unit of thepersonal computer receiving the key data and using the key data as apassword, it is possible to identify a person according to a passwordhaving a sufficient length. This, for example, may be utilized in aprocess for returning from a screen saver (to the screen underoperation). Consequently, it is possible to protect personal computersfrom unfair use.

[0157] The invention is not limited to the above embodiments and variousmodifications can be made without departing from the spirit and thescope of the invention. Any improvement may be made in part or all ofthe components.

What is claimed is:
 1. A first keylock switch comprising: first and second terminals each to be a point of making contact electrically; charge storing means connected between said first and second terminals, for being charged by power supplied through said first and second terminals; a memory for storing key data having a predetermined length; and read means for reading said key data stored in said memory by utilizing the power supply from said charge storing means, to output said key data through said first and second terminals.
 2. A second keylock switch comprising: a metal key for operating mechanical components provided to a lock; an insulating part for covering at least a part of a head part provided to said metal key; and a keylock switch circuit disposed inside said insulating part, wherein said keylock switch circuit includes: a first terminal disposed at a portion at which said insulating part and said metal key keep contact with each other; a second terminal disposed on a surface of said insulating part at which said insulating part is out of contact from said metal key; charge storing means connected between said first and second terminals, for being charged by power supplied through said first and second terminals; a memory for storing key data having a predetermined length; and read means for reading said key data stored in said memory by utilizing the power supply from said charge storing means, to output said key data through said first and second terminals.
 3. A first keylock switch system comprising: a first electronic keylock for actuating a locking operation or a releasing operation in response to acceptance of key data; and a first keylock switch for inputting said key data to said first electronic keylock, wherein said first keylock switch includes: first and second terminals each to be a point of making contact electrically; charge storing means connected between said first and second terminals, for being charged by power supplied through said first and second terminals; a memory for storing key data having a predetermined length; and read means for reading said key data stored in said memory by utilizing the power supply from said charge storing means, to output said key data through said first and second terminals, and wherein said first electronic keylock includes: third and fourth terminals for forming two junctions by contacting said first and second terminals, respectively; a power source for supplying driving power to said keylock switch through said third and fourth terminals; and detecting means for detecting said key data from a signal between said third and fourth terminals.
 4. A second keylock switch system comprising: a second electronic keylock for actuating a locking operation or a releasing operation in response to acceptance of key data; and a second keylock switch for inputting said key data to said second electronic keylock, wherein said second keylock switch includes: a metal key for operating mechanical components provided to a lock; an insulating part for covering at least a part of a head portion provided to said metal key; and a keylock switch circuit disposed inside said insulating part, wherein said keylock switch circuit includes: a first terminal disposed at a portion at which said insulating part and said metal key keep contact with each other; a second terminal disposed on a surface of said insulating part at which said insulating part is out of contact with each other; charge storing means connected between said first and second terminals, for being charged by power supplied through said first and second terminals; a memory for storing key data having a predetermined length; and read means for receiving the supply of power stored in said charge storing means, reading said key data stored in said memory, and outputting said key data through said first and second terminals, and wherein said second electronic keylock includes: a third terminal so disposed as to keep contact with a metal member to contact said metal key; a fourth terminal for forming one of junctions, by contacting said second terminal; a power source for supplying driving power to said keylock switch through said third and fourth terminals; and detecting means for detecting said key data from a signal between said third and fourth terminals.
 5. The first keylock switch according to claim 1, wherein said first keylock switch is a third keylock switch further comprising rectifying means for regulating power supplying direction between said first terminal and said charge storing means and between said second terminal and said charge storing means.
 6. The second keylock switch according to claim 2, wherein said second keylock switch is a fourth keylock switch further comprising rectifying means for regulating power supplying direction between said first terminal and said charge storing means and between said second terminal and said charge storing means.
 7. The first keylock switch system according to claim 3, wherein said first keylock switch is a third keylock switch further comprising rectifying means for regulating power supplying direction between said first terminal and said charge storing means and between said second terminal and said charge storing means.
 8. The second keylock switch system according to claim 4, wherein said second keylock switch is a fourth keylock switch further comprising rectifying means for regulating power supplying direction between said first terminal and said charge storing means and between said second terminal and said charge storing means.
 9. The first keylock switch system according to claim 3, wherein said first keylock switch is a fifth keylock switch further comprising discharging means for discharging power remaining in said charge storing means provided in said keylock switch in response to release of said two junctions.
 10. The second keylock switch system according to claim 4, wherein said second keylock switch is a sixth keylock switch further comprising discharging means for discharging power remaining in said charge storing means provided in said keylock switch in response to release of said two junctions.
 11. The first keylock switch system according to claim 3, wherein said first electronic keylock is a third electronic keylock further comprising isolating means for isolating from said power source an AC signal between said third terminal and said fourth terminal.
 12. The second keylock switch system according to claim 4, wherein said second electronic keylock is a fourth electronic keylock further comprising isolating means for isolating from said power source an AC signal between said third terminal and said fourth terminal. 